bgp/rib-impl/src/main/java/org/opendaylight/protocol/bgp/rib/impl/BGPSessionImpl.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.protocol.bgp.rib.impl;
   9
  10 import com.google.common.annotations.VisibleForTesting;
  11 import com.google.common.base.MoreObjects;
  12 import com.google.common.base.MoreObjects.ToStringHelper;
  13 import com.google.common.base.Optional;
  14 import com.google.common.base.Preconditions;
  15 import com.google.common.collect.Lists;
  16 import com.google.common.collect.Sets;
  17 import io.netty.channel.Channel;
  18 import io.netty.channel.ChannelFuture;
  19 import io.netty.channel.ChannelFutureListener;
  20 import io.netty.channel.ChannelHandlerContext;
  21 import io.netty.channel.ChannelPipeline;
  22 import io.netty.channel.SimpleChannelInboundHandler;
  23 import java.io.IOException;
  24 import java.nio.channels.NonWritableChannelException;
  25 import java.util.Date;
  26 import java.util.List;
  27 import java.util.Set;
  28 import java.util.concurrent.TimeUnit;
  29 import javax.annotation.concurrent.GuardedBy;
  30 import org.opendaylight.controller.config.yang.bgp.rib.impl.BgpSessionState;
  31 import org.opendaylight.protocol.bgp.parser.AsNumberUtil;
  32 import org.opendaylight.protocol.bgp.parser.BGPDocumentedException;
  33 import org.opendaylight.protocol.bgp.parser.BGPError;
  34 import org.opendaylight.protocol.bgp.parser.BgpExtendedMessageUtil;
  35 import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
  36 import org.opendaylight.protocol.bgp.parser.spi.MultiPathSupport;
  37 import org.opendaylight.protocol.bgp.parser.spi.pojo.MultiPathSupportImpl;
  38 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
  39 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
  40 import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionStatistics;
  41 import org.opendaylight.protocol.bgp.rib.spi.BGPSession;
  42 import org.opendaylight.protocol.bgp.rib.spi.BGPSessionListener;
  43 import org.opendaylight.protocol.bgp.rib.spi.BGPTerminationReason;
  44 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.AsNumber;
  45 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Address;
  46 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
  49 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder;
  50 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
  51 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Update;
  52 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParameters;
  53 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilities;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParameters;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.CParameters1;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.RouteRefresh;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.AddPathCapability;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.MultiprotocolCapability;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.add.path.capability.AddressFamilies;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
  62 import org.opendaylight.yangtools.yang.binding.Notification;
  63 import org.slf4j.Logger;
  64 import org.slf4j.LoggerFactory;
  65
  66 @VisibleForTesting
  67 public class BGPSessionImpl extends SimpleChannelInboundHandler<Notification> implements BGPSession, BGPSessionStatistics, AutoCloseable {
  68
  69     private static final Logger LOG = LoggerFactory.getLogger(BGPSessionImpl.class);
  70
  71     private static final Notification KEEP_ALIVE = new KeepaliveBuilder().build();
  72
  73     private static final int KA_TO_DEADTIMER_RATIO = 3;
  74
  75     private static final String EXTENDED_MSG_DECODER = "EXTENDED_MSG_DECODER";
  76
  77     static final String END_OF_INPUT = "End of input detected. Close the session.";
  78
  79     /**
  80      * Internal session state.
  81      */
  82     public enum State {
  83         /**
  84          * The session object is created by the negotiator in OpenConfirm state. While in this state, the session object
  85          * is half-alive, e.g. the timers are running, but the session is not completely up, e.g. it has not been
  86          * announced to the listener. If the session is torn down in this state, we do not inform the listener.
  87          */
  88         OPEN_CONFIRM,
  89         /**
  90          * The session has been completely established.
  91          */
  92         UP,
  93         /**
  94          * The session has been closed. It will not be resurrected.
  95          */
  96         IDLE,
  97     }
  98
  99     /**
 100      * System.nanoTime value about when was sent the last message.
 101      */
 102     @VisibleForTesting
 103     private long lastMessageSentAt;
 104
 105     /**
 106      * System.nanoTime value about when was received the last message
 107      */
 108     private long lastMessageReceivedAt;
 109
 110     private final BGPSessionListener listener;
 111
 112     private final BGPSynchronization sync;
 113
 114     private int kaCounter = 0;
 115
 116     private final Channel channel;
 117
 118     @GuardedBy("this")
 119     private State state = State.OPEN_CONFIRM;
 120
 121     private final Set<BgpTableType> tableTypes;
 122     private final List<AddressFamilies> addPathTypes;
 123     private final int holdTimerValue;
 124     private final int keepAlive;
 125     private final AsNumber asNumber;
 126     private final Ipv4Address bgpId;
 127     private final BGPPeerRegistry peerRegistry;
 128     private final ChannelOutputLimiter limiter;
 129
 130     private BGPSessionStats sessionStats;
 131
 132     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final BGPSessionPreferences localPreferences,
 133             final BGPPeerRegistry peerRegistry) {
 134         this(listener, channel, remoteOpen, localPreferences.getHoldTime(), peerRegistry);
 135         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.of(localPreferences), this.tableTypes, this.addPathTypes);
 136     }
 137
 138     public BGPSessionImpl(final BGPSessionListener listener, final Channel channel, final Open remoteOpen, final int localHoldTimer,
 139             final BGPPeerRegistry peerRegistry) {
 140         this.listener = Preconditions.checkNotNull(listener);
 141         this.channel = Preconditions.checkNotNull(channel);
 142         this.limiter = new ChannelOutputLimiter(this);
 143         this.channel.pipeline().addLast(this.limiter);
 144         this.holdTimerValue = (remoteOpen.getHoldTimer() < localHoldTimer) ? remoteOpen.getHoldTimer() : localHoldTimer;
 145         LOG.info("BGP HoldTimer new value: {}", this.holdTimerValue);
 146         this.keepAlive = this.holdTimerValue / KA_TO_DEADTIMER_RATIO;
 147         this.asNumber = AsNumberUtil.advertizedAsNumber(remoteOpen);
 148         this.peerRegistry = peerRegistry;
 149         final boolean enableExMess = BgpExtendedMessageUtil.advertizedBgpExtendedMessageCapability(remoteOpen);
 150         if (enableExMess) {
 151             this.channel.pipeline().replace(BGPMessageHeaderDecoder.class, EXTENDED_MSG_DECODER, BGPMessageHeaderDecoder.getExtendedBGPMessageHeaderDecoder());
 152         }
 153
 154         final Set<TablesKey> tts = Sets.newHashSet();
 155         final Set<BgpTableType> tats = Sets.newHashSet();
 156         final List<AddressFamilies> addPathCapabilitiesList = Lists.newArrayList();
 157         if (remoteOpen.getBgpParameters() != null) {
 158             for (final BgpParameters param : remoteOpen.getBgpParameters()) {
 159                 for (final OptionalCapabilities optCapa : param.getOptionalCapabilities()) {
 160                     final CParameters cParam = optCapa.getCParameters();
 161                     if ( cParam.getAugmentation(CParameters1.class) == null) {
 162                         continue;
 163                     }
 164                     if(cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability() != null) {
 165                         final MultiprotocolCapability multi = cParam.getAugmentation(CParameters1.class).getMultiprotocolCapability();
 166                         final TablesKey tt = new TablesKey(multi.getAfi(), multi.getSafi());
 167                         LOG.trace("Added table type to sync {}", tt);
 168                         tts.add(tt);
 169                         tats.add(new BgpTableTypeImpl(tt.getAfi(), tt.getSafi()));
 170                     } else if (cParam.getAugmentation(CParameters1.class).getAddPathCapability() != null) {
 171                         final AddPathCapability addPathCap = cParam.getAugmentation(CParameters1.class).getAddPathCapability();
 172                         addPathCapabilitiesList.addAll(addPathCap.getAddressFamilies());
 173                     }
 174                 }
 175             }
 176         }
 177
 178         this.sync = new BGPSynchronization(this.listener, tts);
 179         this.tableTypes = tats;
 180         this.addPathTypes = addPathCapabilitiesList;
 181
 182         if (! this.addPathTypes.isEmpty()) {
 183             final ChannelPipeline pipeline = this.channel.pipeline();
 184             final BGPByteToMessageDecoder decoder = pipeline.get(BGPByteToMessageDecoder.class);
 185             decoder.addDecoderConstraint(MultiPathSupport.class,
 186                     MultiPathSupportImpl.createParserMultiPathSupport(this.addPathTypes));
 187         }
 188
 189         if (this.holdTimerValue != 0) {
 190             channel.eventLoop().schedule(new Runnable() {
 191                 @Override
 192                 public void run() {
 193                     handleHoldTimer();
 194                 }
 195             }, this.holdTimerValue, TimeUnit.SECONDS);
 196
 197             channel.eventLoop().schedule(new Runnable() {
 198                 @Override
 199                 public void run() {
 200                     handleKeepaliveTimer();
 201                 }
 202             }, this.keepAlive, TimeUnit.SECONDS);
 203         }
 204         this.bgpId = remoteOpen.getBgpIdentifier();
 205         this.sessionStats = new BGPSessionStats(remoteOpen, this.holdTimerValue, this.keepAlive, channel, Optional.<BGPSessionPreferences>absent(),
 206                 this.tableTypes, this.addPathTypes);
 207     }
 208
 209     @Override
 210     public synchronized void close() {
 211         if (this.state != State.IDLE) {
 212             this.writeAndFlush(new NotifyBuilder().setErrorCode(BGPError.CEASE.getCode()).setErrorSubcode(BGPError.CEASE.getSubcode()).build());
 213         }
 214         this.closeWithoutMessage();
 215     }
 216
 217     /**
 218      * Handles incoming message based on their type.
 219      *
 220      * @param msg incoming message
 221      */
 222     synchronized void handleMessage(final Notification msg) throws BGPDocumentedException {
 223         // Update last reception time
 224         this.lastMessageReceivedAt = System.nanoTime();
 225         this.sessionStats.updateReceivedMsgTotal();
 226
 227         if (msg instanceof Open) {
 228             // Open messages should not be present here
 229             this.terminate(new BGPDocumentedException(null, BGPError.FSM_ERROR));
 230         } else if (msg instanceof Notify) {
 231             // Notifications are handled internally
 232             LOG.info("Session closed because Notification message received: {} / {}", ((Notify) msg).getErrorCode(),
 233                     ((Notify) msg).getErrorSubcode());
 234             this.closeWithoutMessage();
 235             this.listener.onSessionTerminated(this, new BGPTerminationReason(
 236                     BGPError.forValue(((Notify) msg).getErrorCode(), ((Notify) msg).getErrorSubcode())));
 237             this.sessionStats.updateReceivedMsgErr((Notify) msg);
 238         } else if (msg instanceof Keepalive) {
 239             // Keepalives are handled internally
 240             LOG.trace("Received KeepAlive messsage.");
 241             this.kaCounter++;
 242             this.sessionStats.updateReceivedMsgKA();
 243             if (this.kaCounter >= 2) {
 244                 this.sync.kaReceived();
 245             }
 246         } else if (msg instanceof RouteRefresh) {
 247             this.listener.onMessage(this, msg);
 248             this.sessionStats.updateReceivedMsgRR();
 249         } else if (msg instanceof Update) {
 250             this.listener.onMessage(this, msg);
 251             this.sync.updReceived((Update) msg);
 252             this.sessionStats.updateReceivedMsgUpd();
 253         } else {
 254             LOG.warn("Ignoring unhandled message: {}.", msg.getClass());
 255         }
 256     }
 257
 258     synchronized void endOfInput() {
 259         if (this.state == State.UP) {
 260             LOG.info(END_OF_INPUT);
 261             this.listener.onSessionDown(this, new IOException(END_OF_INPUT));
 262         }
 263     }
 264
 265     @GuardedBy("this")
 266     private ChannelFuture writeEpilogue(final ChannelFuture future, final Notification msg) {
 267         future.addListener(
 268             new ChannelFutureListener() {
 269                 @Override
 270                 public void operationComplete(final ChannelFuture f) {
 271                     if (!f.isSuccess()) {
 272                         LOG.warn("Failed to send message {} to socket {}", msg, BGPSessionImpl.this.channel, f.cause());
 273                     } else {
 274                         LOG.trace("Message {} sent to socket {}", msg, BGPSessionImpl.this.channel);
 275                     }
 276                 }
 277             });
 278         this.lastMessageSentAt = System.nanoTime();
 279         this.sessionStats.updateSentMsgTotal();
 280         if (msg instanceof Update) {
 281             this.sessionStats.updateSentMsgUpd();
 282         } else if (msg instanceof Notify) {
 283             this.sessionStats.updateSentMsgErr((Notify) msg);
 284         }
 285         return future;
 286     }
 287
 288     void flush() {
 289         this.channel.flush();
 290     }
 291
 292     synchronized void write(final Notification msg) {
 293         try {
 294             writeEpilogue(this.channel.write(msg), msg);
 295         } catch (final Exception e) {
 296             LOG.warn("Message {} was not sent.", msg, e);
 297         }
 298     }
 299
 300     synchronized ChannelFuture writeAndFlush(final Notification msg) {
 301         if (isWritable()) {
 302             return writeEpilogue(this.channel.writeAndFlush(msg), msg);
 303         }
 304         return this.channel.newFailedFuture(new NonWritableChannelException());
 305     }
 306
 307     private synchronized void closeWithoutMessage() {
 308         LOG.info("Closing session: {}", this);
 309         removePeerSession();
 310         this.channel.close().addListener(new ChannelFutureListener() {
 311             @Override
 312             public void operationComplete(final ChannelFuture future) throws Exception {
 313                 Preconditions.checkArgument(future.isSuccess(), "Channel failed to close: %s", future.cause());
 314             }
 315         });
 316         this.state = State.IDLE;
 317     }
 318
 319     /**
 320      * Closes BGP session from the parent with given reason. A message needs to be sent, but parent doesn't have to be
 321      * modified, because he initiated the closing. (To prevent concurrent modification exception).
 322      *
 323      * @param e BGPDocumentedException
 324      */
 325     private synchronized void terminate(final BGPDocumentedException e) {
 326         final BGPError error = e.getError();
 327         final byte[] data = e.getData();
 328         final NotifyBuilder builder = new NotifyBuilder().setErrorCode(error.getCode()).setErrorSubcode(error.getSubcode());
 329         if (data != null && data.length != 0) {
 330             builder.setData(data);
 331         }
 332         this.writeAndFlush(builder.build());
 333         this.closeWithoutMessage();
 334
 335         this.listener.onSessionTerminated(this, new BGPTerminationReason(error));
 336     }
 337
 338     private void removePeerSession() {
 339         if (this.peerRegistry != null) {
 340             this.peerRegistry.removePeerSession(StrictBGPPeerRegistry.getIpAddress(this.channel.remoteAddress()));
 341         }
 342     }
 343
 344     /**
 345      * If HoldTimer expires, the session ends. If a message (whichever) was received during this period, the HoldTimer
 346      * will be rescheduled by HOLD_TIMER_VALUE + the time that has passed from the start of the HoldTimer to the time at
 347      * which the message was received. If the session was closed by the time this method starts to execute (the session
 348      * state will become IDLE), then rescheduling won't occur.
 349      */
 350     private synchronized void handleHoldTimer() {
 351         if (this.state == State.IDLE) {
 352             return;
 353         }
 354
 355         final long ct = System.nanoTime();
 356         final long nextHold = this.lastMessageReceivedAt + TimeUnit.SECONDS.toNanos(this.holdTimerValue);
 357
 358         if (ct >= nextHold) {
 359             LOG.debug("HoldTimer expired. {}", new Date());
 360             this.terminate(new BGPDocumentedException(BGPError.HOLD_TIMER_EXPIRED));
 361         } else {
 362             this.channel.eventLoop().schedule(new Runnable() {
 363                 @Override
 364                 public void run() {
 365                     handleHoldTimer();
 366                 }
 367             }, nextHold - ct, TimeUnit.NANOSECONDS);
 368         }
 369     }
 370
 371     /**
 372      * If KeepAlive Timer expires, sends KeepAlive message. If a message (whichever) was send during this period, the
 373      * KeepAlive Timer will be rescheduled by KEEP_ALIVE_TIMER_VALUE + the time that has passed from the start of the
 374      * KeepAlive timer to the time at which the message was sent. If the session was closed by the time this method
 375      * starts to execute (the session state will become IDLE), that rescheduling won't occur.
 376      */
 377     private synchronized void handleKeepaliveTimer() {
 378         if (this.state == State.IDLE) {
 379             return;
 380         }
 381
 382         final long ct = System.nanoTime();
 383         long nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 384
 385         if (ct >= nextKeepalive) {
 386             this.writeAndFlush(KEEP_ALIVE);
 387             nextKeepalive = this.lastMessageSentAt + TimeUnit.SECONDS.toNanos(this.keepAlive);
 388             this.sessionStats.updateSentMsgKA();
 389         }
 390         this.channel.eventLoop().schedule(new Runnable() {
 391             @Override
 392             public void run() {
 393                 handleKeepaliveTimer();
 394             }
 395         }, nextKeepalive - ct, TimeUnit.NANOSECONDS);
 396     }
 397
 398     @Override
 399     public final String toString() {
 400         return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
 401     }
 402
 403     protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
 404         toStringHelper.add("channel", this.channel);
 405         toStringHelper.add("state", this.getState());
 406         return toStringHelper;
 407     }
 408
 409     @Override
 410     public Set<BgpTableType> getAdvertisedTableTypes() {
 411         return this.tableTypes;
 412     }
 413
 414     @Override
 415     public List<AddressFamilies> getAdvertisedAddPathTableTypes() {
 416         return this.addPathTypes;
 417     }
 418
 419     protected synchronized void sessionUp() {
 420         this.sessionStats.startSessionStopwatch();
 421         this.state = State.UP;
 422         this.listener.onSessionUp(this);
 423     }
 424
 425     public synchronized State getState() {
 426         return this.state;
 427     }
 428
 429     @Override
 430     public final Ipv4Address getBgpId() {
 431         return this.bgpId;
 432     }
 433
 434     @Override
 435     public final AsNumber getAsNumber() {
 436         return this.asNumber;
 437     }
 438
 439     synchronized boolean isWritable() {
 440         return this.channel != null && this.channel.isWritable();
 441     }
 442
 443     void schedule(final Runnable task) {
 444         Preconditions.checkState(this.channel != null);
 445         this.channel.eventLoop().submit(task);
 446     }
 447
 448     @VisibleForTesting
 449     protected synchronized void setLastMessageSentAt(final long lastMessageSentAt) {
 450         this.lastMessageSentAt = lastMessageSentAt;
 451     }
 452
 453     @Override
 454     public synchronized BgpSessionState getBgpSessionState() {
 455         return this.sessionStats.getBgpSessionState(this.state);
 456     }
 457
 458     @Override
 459     public synchronized void resetSessionStats() {
 460         this.sessionStats.resetStats();
 461     }
 462
 463     public ChannelOutputLimiter getLimiter() {
 464         return this.limiter;
 465     }
 466
 467     @Override
 468     public final void channelInactive(final ChannelHandlerContext ctx) {
 469         LOG.debug("Channel {} inactive.", ctx.channel());
 470         this.endOfInput();
 471
 472         try {
 473             super.channelInactive(ctx);
 474         } catch (final Exception e) {
 475             throw new IllegalStateException("Failed to delegate channel inactive event on channel " + ctx.channel(), e);
 476         }
 477     }
 478
 479     @Override
 480     protected final void channelRead0(final ChannelHandlerContext ctx, final Notification msg) {
 481         LOG.debug("Message was received: {}", msg);
 482         try {
 483             this.handleMessage(msg);
 484         } catch (final BGPDocumentedException e) {
 485             this.terminate(e);
 486         }
 487     }
 488
 489     @Override
 490     public final void handlerAdded(final ChannelHandlerContext ctx) {
 491         this.sessionUp();
 492     }
 493
 494     @Override
 495     public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
 496         LOG.warn("BGP session encountered error", cause);
 497         if (cause.getCause() instanceof BGPDocumentedException) {
 498             this.terminate((BGPDocumentedException) cause.getCause());
 499         } else {
 500             this.close();
 501         }
 502     }
 503 }